This may be mean, since poor Elisabetta is not herself an Oscar invitee--she's a "plus one," and it is hardly fair to assault someone who's only claim to our attention is that she is dating George Clooney.
That's a fair assessment, but this is a fashion mistake. Maybe we can blame somebody else for it, though.
It's her undergarment. You can see it pretty clearly here, just as I saw it on television. It's a corset or something, with a panel that runs in a triangle down her abdomen and points straight at her ladybits.
Now, maybe, she decided she wanted to wear something sexy and glamorous under her red satin gown, something that would make her feel more fabulous than a pair of Spanx, and really, who can blame her? I mean, why pull a Bridget Jones buzzkill on Oscar night with a pair of practical and unattractive underpants.
Fortunately for her, somebody must have spotted it early in the evening and whispered in her ear, because most of the rest of the night she has her clutch or her wrap conveniently posed to hide the lines.